In-situ transformation into MoP/MoS2 heterogeneous structure with rich S-vacancy enhanced hydrogen evolution reaction

The surface modification strategy has broken through the restriction of hydrogen evolution activity caused by low conductivity inert surfaces of MoS2 during hydrogen evolution reaction. In this work, a new strategy for regulating the interface structure between MoS2 and MoP using sulfur vacancy is proposed, which is derived from the synthesis of molybdenum disulfide nanotubes with rich S-vacancy (Sv-MoS2) by reduction. Subsequently, Sv-MoS2 was phosphated by introducing a P source, and the obtained (MoP/Sv-MoS2-8) composite. The introduction of P atoms provides more active sites for hydrogen adsorption and desorption by replacing S atoms to form (Mo-P) covalent bonds, further increase the number of S vacancies to activate the inert interface. The synthesized MoP/Sv-MoS2-8 has excellent catalytic activity and good cyclic stability, showing a lower Tafel slope of 60 mV·dec−1 at a current density of 10 mA·cm−2, and no potential attenuation after the cyclic stability test for 24 h. The excellent HER performance is mainly due to the synergistic effect of P atom doping and S vacancy, which greatly reduces the energy barrier of the Volmer step and the adsorption/desorption of the H* intermediate step.